XP requires more system resources to run. It's an undenyable fact. Win95 will boot and run faster than any other windows version, even if by unnoticable figures, simply because it's smaler. Win98 is somewhere in between. Instablity isn't a factor... XP takes more sources.
I've never actually USED XP, but I've seen it on several PC's, usually averaging at 87% usage. I have run Win98 on 9% and Win2k on about 48% I think...
* Your high priced security consultant\'s plane ticket: $1500
* Your high priced security consultant\'s time: $200/hour
* RealSecure nodes all over your company: $200,000
* Getting owned by 0day: Priceless